The network is being managed by AT&T in a public-private partnership, with AT&T getting access to the new spectrum allocated for the network and FirstNet getting priority use of that spectrum and AT&T's network in times of emergency.

States can opt out of the FirstNet state plan and come up with their own alternative with another partner—a point Verizon has made in launching its own public safety net—but they must be interoperable with FirstNet, which was created by Congress at the recommendation of the 9/11 Commission and funded through FCC spectrum auction proceeds.

Florida could be the next sign-up. According to FirstNet, the state's FirstNet executive committee has recommended opting in.